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Full text of "Making muscadine table wine"

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CONTENTS 

Introduction, 3 
Legal Requirements, 3 
Background Information on Wines, 4 
Equipment and Supplies, 5 
Instructions for Making a Dry Red or 

White Table Wine. 8 
Simplified Instructions for Making 

a Red or White Table Wine, 14 
Use of the Hydrometer and Sugar Calculations, 15 
General Comments, 17 
Home Wine Making Suppliers, 21 
Bibliography. 21 
Useful Conversion Factors in Wine Making, 22 



Prepared by 

Daniel E. Carroll, Department of Food Science, 

North Carolina State University 

Published by 
THE NORTH CAROLINA AGRICULTURAL EXTENSION SERVICE 

North Carolina State University at Raleigh and the U. S. Department of Agricul- 
ture, Cooperating. State University Station, Raleigh, N. C, George Hyatt, Jr., 
Director. Distributed in furtherance of the Acts of Congress of May 8 and June 
30, 1914. 

Circular 602 (Reprint) June 1975 



MaRina Muscacfme 

ime Wine 



u 



INTRODUCTION 

Muscadine grapes {Vitis rotundifolia) are native to the South 
and have become an increasingly important commodity in North 
Carolina since the early 1960's. The principal commercial outlet 
for Muscadine grapes is wine. These wines when made properly 
have a unique flavor and aroma that is valued highly by those 
familiar with the Muscadine grape. 

In the past several years we have received numerous requests 
from North Carolinians seeking information on making Muscadine 
wines. It is hoped that this publication will be of benefit to those 
individuals who have found wine making to be a fascinating and 
enjoyable hobby. 

Two sets of instructions are presented. The detailed instructions 
are for the serious amateur who desires to produce the finest 
wines possible at home and with the lowest rate of failure. The 
simplified instructions are for making Muscadine wine at home 
with a minimum of equipment, supplies and attention to detail 
(see pages 14-15). 

Although these instructions are specifically for use on Musca- 
dine grapes, they can be used successfully on other types of 
grapes grown in North Carolina such as Concords and the new 
French-American hybrids. 



LEGAL REQUIREMENTS 

Any head of a family household can legally make up to 200 
gallons of wine for home consumption. However, he is required 
by law to file in duplicate two copies of Form 1541 with the In- 



ternal Revenue Service Regional Office five days prior to begin- 
ning wine production. The address of our Regional Office is: 

Assistant Regional Commissioner 
Internal Revenue Service 
Alcohol and Tobacco Tax Division 
Federal Office Building 
275 Peachtree Street 
Atlanta, Georgia 30303 



BACKGROUND INFORMATION ON WINES 

Wine is the product of a sound alcoholic fermentation of 
grape juice by yeast. In this process, yeast consume the grape 
sugars and produce ethyl alcohol and carbon dioxide gas. In 
addition, many other chemical substances are produced in small 
quantities which contribute to the flavor and aroma of the wine. 
Flavor and aroma are further enhanced by proper aging of the 
wine. 

There are many different types of wine. Table wine contains 
14% or less ethyl alcohol. It may be either dry or slightly sweet 
and white, red, or pink in color. Table wine seldom contains 
more than about 4% residual sugar after fermentation is com- 
pleted. It is used with food to refresh the palate and complement 
a meal without satisfying the appetite. 

Dry wine is the best type to make in the home because it is 
less likely to spoil than sweet wine, and also it can be sweetened 
at any time by dissolving the desired amount of sugar in it. Red 
wine is made from dark-skinned varieties, such as 'Hunt' or 
'Tarheel', and contains coloring matter extracted from the grape 
skins during fermentation of the crushed grapes "on the skins." 
Pink (rose) wine is also made from dark-skinned varieties, but is 
vinted to contain smaller amounts of coloring matter. White wine 
is usually pale yellow in color and made from green or bronze 
varieties of grapes such as 'Magnolia', Scuppernong', and 'Carlos.' 

Dessert wine contains between 14-24% ethyl alcohol and is pro- 
duced by commercial wineries and not by the amateur wine maker. 
It is usually fortified with brandy to increase the alcohol to the 
desired level. Dessert wines are usually sweet and contain about 
5 to 14% sugar or more. 



Champagne, in the American usage of the term, is a sparkling 
white or pink wine made from dry table wine. It derives its effer- 
vescence solely from a secondary fermentation of the wine with- 
in a closed container. 



EQUIPMENT AND SUPPLIES 

The following basic equipment and supplies are needed in 
order to attain consistent and successful results: 

1. A primary fermentor is an open vessel in which the initial 
fermentation takes place. It must be large enough to accommo- 
date the increase in volume due to foaming which accompanies 
the beginning of active fermentation of the grape juice. These 
vessels may be of any non-toxic and inert material such as glass, 
plastic (polyethylene), wood and ceramic (Figure 1). Metal con- 
tainers, other than stainless steel, must not be used unless they 
are lined with a heavy duty polyethylene bag of suitable size. 




Figure 1. Primary fermentors. 



2. A fermentation lock (water seal) allows the carbon dioxide 
gas (COo) produced during fermentation to escape but prevents 
air from contact with the wine (Figure 2). 





) 


i 






■ 1 



Figure 2. Fermentation locl<s. Jlie one on the left is tiomemade 
whiile the other ones are two-piece commercial plastic 
locks. 



3. A secondary fermentor must be a glass jug, or carboy, or 
wooden barrel that has only one small opening which can be 
fitted with a fermentation lock (Figure 3). The wine is transferred 
to this container 4-5 days after the start of fermentation. 

4. A hydrometer is a simple and inexpensive instrument for 
measuring the amount of sugar in the grape juice (Figure 4). It 
is essential for consistent results in wine making. Its use is ex- 
plained on pages 15-16. 

The sugar content can also be measured with a refractometer. 
It is a highly accurate optical instrument which is very easy to 
use; however, it is expensive to purchase. 

5. Either sodium bisulfile or potassium metabisulfite is used as 
a source of SO-^ to check the growth of undesirable yeast and 
bacteria in the grape juice or wine. It also functions as an anti- 
oxidant in protecting the finished wine from adverse effects of 
excess oxygen. 



/ 




■if ^_ 

Figure 3. Secondary fermentors with fermentation locks in place. 



Figure 4. Hydrometer 
with cylinder. 




6. A plastic or rubber hose about 3/8 inch inside diameter and 
about 6 feet long is needed for siphoning the wine. 

7. A culture of wine yeast is desirable to insure a sound and 
clean fermentation. Montrachet No. 522 is good strain of yeast 
to use. Such cultures are available in powdered form and are 
very easy to use. An acceptable second choice for yeast is baker's 
yeast which is available in any supermarl<et. 

All of the equipment and supplies listed in this section can be 
obtained from wine or scientific supply houses. Also, your local 
pharmacist might be a source of some of the supplies. 



INSTRUCTIONS FOR MAKING A DRY RED OR 
WHITE TABLE WINE 

The instructions that follow are for production of either a dry 
red or white wine from one bushel (about 50 pounds) of Muscadine 
grapes. A red wine must be made from a dark-skinned variety 
of grape such as Hunt' or 'Tarheel' while a white wine should 
be made from a light-skinned variety such as 'Scuppernong', 
'Magnolia', or 'Carlos.' 

Step 1. The grapes should be fully ripe without being overripe 
Unripe grapes are high in acid, low in sugar and flavor, and the 
dark-skinned grapes are poor in color. The grapes should be pro- 
cessed as soon as possible after harvesting. 

Step 2. Remove stems and unripe and rotten fruit. Rinse the 
grapes with cool water and allow to drain. 

Step 3. Crush the grapes. This can be done by spreading the 
grapes in a thin layer in a large flat bottom pan and by crush- 
ing them with a potato masher, rolling pin, or similar tool (Figure 
5). The objective is to crush all the grapes without crushing the 
seeds. Commercial crushers are available. They crush the grapes 
between a pair of aluminum rollers (Figure 6). 

Step 4. Transfer the crushed grapes to a 10 gallon polyethy- 
lene bucket (should be a new one) or some other suitable con- 
tainer. Mix the contents thoroughly. 

Step 5. Remove a sample of the juice and test it for sugar con- 
tent with a hydrometer or refractometer. (See pages 15-16.) 




Figure 5. Crushing grapes by liand. 




Figure 6. Small commercial grape crusher. 




Figure 7. Squeezing grapes 
by liand. 




Figure 8. Small grape press. 



10 



step 6. Dissolve 1/2 level teaspoon of either potassium meta- 
bisulfite or sodium bisulfite in about a pint of the grape juice and 
add it to the bushel of crushed grapes. Mix thoroughly, cover the 
opening of the container with cheesecloth, and wait four hours 
before proceeding to the next step. 

Step 7. Activate a five gram package of dried wine yeast by 
mixing it into one cup of warm grape juice (about 100° F). Add 
it to the crushed grapes and mix. If a wine yeast is not available, 
use dried baker's yeast. Cover the bucket with cheesecloth and 
store it at a constant temperature between 60-75° F. Fermenta- 
tion should begin within 24 hours after addition of the yeast. 

Step 8A. FOR WHITE WINE ONLY. When fermentation begins, 

usually within 24 hours of adding the yeast, immediately proceed 

to Step 9. If the fermentation is allowed to proceed for 4-5 days 

"on the skins", as is done in the manufacture of a red wine, the 

wine will be harsh in character and lack the desired fruity quality. 

Step 8B. FOR RED WINE ONLY. After fermentation begins, 
thoroughly mix the crushed grapes at least twice a day for 4-5 
days. This is known as "breaking up the cap" and it is done to aid 
in the extraction of color (pigment) from the grape skins. 

Step 9. Draw-off the fermenting juice and squeeze the remaining 
skins and pulp through several layers of cheesecloth (Figure 7), 
or use a small grape press if available (Figure 8). When using 
cheesecloth, it is easier to squeeze several small size portions 
rather than try to squeeze the entire mass in one batch. Juice 
yield will usually be about 3V2 gallons for 50 pounds of dark- 
skinned grapes fermented "on the skins" and about 3 gallons or 
less for the light-skinned grapes. 

Step 10. Measure the number of gallons of juice obtained. Cal- 
culate the quantity of sugar you need to add to it to increase the 
original sugar level of the juice, as measured in Step 5, to a level 
of 22%. (See pages 15-16.) Dissolve this quantity of sugar in 1 
to 2 quarts of the juice by gradually warming the mixture with 
stirring on the stove. Return this mixture to the fermenting juice. 

Step 11. Dissolve one pound of sugar in two quarts of warm 
water, add the mixture to the fermenting juice and mix well. This 
dilution is known as amelioration. Cover the opening of the pri- 
mary fermentor with cheesecloth and wait for 48 hours before 
proceeding to Step 12. 



11 



step 12. Transfer the juice to 1 gallon glass jugs, or preferably, 
to a 3 gallon glass carboy and 1 or more gallon jugs if needed. 
Fill tfiese containers about 95% full and add a fermentation lock 
(water seal). This is a most important step because the lock allows 
carbon dioxide to escape from the jugs, excludes air from the 
wine, and prevents the wine from turning to vinegar. 

Step 13. Store the fermenting juice at a constant temperature 
between 60-75" F for about 2 months (October-November) or until 
all bubbling in the fermentation lock stops and the wine begins 
to clear. The lower temperature (60" F) is desirable for white 
wine fermentation. Important - the fermentation lock must be 
kept on the containers at all times from now on or the wine will 
probably spoil. 

Step 14. Siphon the wine from the sediment into clean car- 
boys or gallon jugs (Figure 9). Replace the fermentation lock, and 
store the wine at 60 to 70° F for 1 month (December). 

Step 15. Siphon the wine from the sediment into clean carboys 
or gallon jugs. 

Step 16. Dose the wine with potassium metabisulfite or sodium 
bisulfite at the rate of Vs level teaspoon for every 3 gallons of 
wine. 




Figure 9. 

Siphoning the wine on first 
racking. Note the outlet of 
the hose is held near the 
top of the container. This 
is to allow slight aeration 
of the wine but it is done 
only at the first racking. 



12 



step 17. Store the wine in a cold place in the basement or in 
the barn at a temperature of 20-40 F for a period of 2 months 
(January-February). The cold temperature encourages natural 
clarification of the wine. It also helps to eliminate excess potas- 
sium bitartrate, called "wine stones", which will appear as 
crystals in the bottom of the container. 

Step 18. Siphon the clear wine from the sediment into clean 
containers (Figure 10). Replace the fermentation locks and store 
the wine at cool room temperatures 60-70" F for 2 months (March- 
April). The wine will probably deposit more sediment during this 
period. Repeat this step if necessary (May-June). 

Step 19. Repeat the siphoning step and dose the wine with 
potassium metabisulfite or sodium bisulfite at the rate of Vs level 
teaspoon for every 3 gallons. 

Step 20. Siphon the clear wine into clean wine bottles. The 
bottles should be tightly corked. (See pages 18-20.) For a second 
choice, clean soda pop bottles can be used and sealed with 
crown caps or screw caps. The wine can be consumed after 
storage for 1 month in the bottle, but will continue to improve in 
quality with age. Additional sediment may deposit in the bottle 
during aging. This is normal and the clear wine can be carefully 
poured from it. 



Figure 10. 

Siphoning the wine on 
second and all subse- 
quent rackings. Note the 
outlet of the hose is held 
to the bottom of the con- 
tainer thus minimizing 
aeration of the wine. 




13 



SIMPLIFIED INSTRUCTIONS FOR MAKING 
A RED OR WHITE TABLE WINE 

The instructions given in this section are for making Muscadine 
wines at home with an absolute minimum of equipment and care. 
However, the more detailed instructions given previously are the 
recommended ones and will usually yield a superior product with 
lower rate of failure. 

Follow the procedure given in the previous section (see pages 
8-13) with the following changes: 

Steps 1-4 No Change. 

Steps 5-6 Omit. 

Steps 7-9 No change. 

Steps 10-11 Omit and substitute the following step. 

Measure the number of gallons of fermenting juice obtained 
from Step 9 and determine the total amount of sugar you need 
to add from the following table. 

7ofa/ Number of Gallons Total Amount Of 

Of Fermenting Juice Sugar to Add 



4 4 lbs. 

3V2 3 lbs. 10 oz. 

3 3 lbs. 4 oz. 

2V2 2 lbs. 14 oz. 

2 2 lbs. 8oz. 



Dissolve the sugar in 2 quarts of hot water and allow the sirup 
to cool. Add it to the fermenting juice and mix well. Cover the 
opening of the primary fermentor with cheesecloth and wait for 
48 hours before proceeding to step 12. 

Step 12. There is no change in this step. If you do not have a 
fermentation lock (water seal) you can plug the opening of the 
containers with a wad of non-absorbent sterile cotton as a substi- 
tute. This is not as satisfactory as the use of a fermentation lock, 
however. In either case, the containers must be kept full and the 
fermentation lock or cotton plug kept in place from now on or the 
wine will surely spoil. 



14 



steps 13-15 No change. 

Step 16 Omit. 

Steps 17-18 No change. The wine can be used at this time 

if desired. 
Step 19 Omit. 

Step 20 No change. 



USE OF THE HYDROMETER AND 
SUGAR CALCULATIONS 

Fresh iViuscadine grape juice usually contains 11 to 17% sugar 
which is less than is desirable to make a quality wine; therefore, 
additional sugar must be added. Grape juice should contain 
about 20 to 22% sugar to make a satisfactory wine. If the juice is 
deficient in sugar, the resulting wine will be thin in character and 
will spoil easily. If too much sugar is added to the juice, the fer- 
mentation process may proceed with great difficulty and never 
goto completion. Therefore, it is of great value to know the 
amount of sugar present in the juice prior to fermentation in 
order to be able to calculate and add the exact amount of sugar 
necessary to increase the level to 22%. 

The amount of sugar in the juice is measured with a hydro- 
meter (a refractometer can be used if one is available) and can 
be expressed in several different terms, each having essentially 
the same meaning. They are: 

% sugar (by weight) = "Brix = 'Balling 

For example, 22 pounds of pure sugar (sucrose) dissolved in 
78 pounds of water yields a 22% sugar sirup having a "Brix = 
22 or a "Balling = 22. 

To use the hydrometer, a sample of grape juice is filled into a 
tall glass cylinder and the hydrometer is immersed in it (Figure 4). 
Twirl the hydrometer gently to dislodge air bubbles adhering to it 
and to insure it is free-floating. When it comes to rest, read the 
value on the stem of the hydrometer at eye level and at the point 
where the stem emerges from the juice. The temperature of the 
juice should be about 70° F or the true value of the reading may be 
measurably affected. 

The exact amount of sugar to add to the juice can be calcu- 
lated by the use of the following formula: 



15 



0.22 X wt. of juice - wt. of sugar in juice 

S = 

0.78 

where, 

S = the pounds of sugar needed to raise the sugar content of 

the juice to 22%. 
wt of juice = the weight of juice when it is separated from the 

skins, seeds, and pulp after the start of fermentation, 
wt. of juice X % sugar in the juice 
wt of sugar in juice= 

100 

An example of how to use this formula: 

A sample of Muscadine grape juice, drawn from a bushel of 
freshly crushed grapes was found to contain 14% sugar when 
tested with a hydrometer. After the start of fermentation, 33 pounds 
of fermenting juice was separated from the skins, seeds, and 
pulp. How much sugar should be added to the 33 pounds of 
juice to increase the initial sugar level of the juice from 14 to 
22% ? 

First, determine the number of pounds of sugar contained in 
33 pounds of unfermented juice. 

33 pounds x 14% sugar 462 

wt. of sugar in juice = = = 4.62 pounds. 

100 100 



Next, 



0.22 X wt. of juice - 4.62 pounds 

S= 

0.78 

0.22 X 33 pounds -4.62 pounds 

S= 

0.78 

7.26 pounds — 4.62 pounds 

S= 

0.78 

2.64 



0.78 pounds = 3.4 pounds 

Therefore, 3.4 pounds of sugar should be dissolved in the 33 
pounds of fermenting juice. 



16 



GENERAL COMMENTS 



Clean Equipment 

All equipment used in wine making should be clean and free 
from off-odors. If a detergent is used in washing glassware, all 
traces of it should be removed by thorough rinsing with tap 
water. White wines are especially prone to acquiring off-odors and 
flavors from contaminated equipment. 

Alternate Procedure for Making White Wine 

A lighter-bodied and fruitier white wine can be made from juice 
that is separated from the grapes immediately after crushing. If 
this is done, however, the home wine maker should be prepared 
to accept a lower yield of juice. It is very difficult to extract the 
juice from freshly crushed Muscadine grapes because the pulp 
is thick and slippery. Fermentation of the crushed grapes for a 
short period of time greatly facilitates juice extraction. 

In making white wine by the alternate procedure, follow steps 1- 
4. Next, immediately press-out the juice from the crushed grapes. 
Steps 5-7 are the same except substitute V4 level teaspoon of 
potassium metabisulfite or sodium bisulfite in step 6. Omit steps 
8A and 9. Steps 10-20 are unchanged. 

Making a Pink Wine 

Pink wine, also called rose wine, can be made from dark- 
skinned varieties of Muscadine grapes by following the proce- 
dure given for making a white wine. Enough pigment is usually 
extracted from the grape skins within 24 hours after crushing 
the grapes to give the desired color in the finished wine. 

Fining of Muscadine Wines 

Muscadine wines usually clear easily on their own once fer- 
mentation is finished and the wine is left undisturbed. However, 
occasionally a given batch of wine remains hazy. In these cases, 
good results are often obtained by fining the wine with unflavored 
gelatin and tannin (tannic acid powder). Gelatin and tannin com- 
bine chemically in solution to form a coarse precipitate. The fine 
particles which cause haze in the wine are entrapped in the 
gelatin-tannin complex and thus are removed from the wine. 

To fine a white wine, use % level teaspoon of tannin and Va level 
teaspoon of unflavored gelatin (approximately equal weights of 
each) for every 2 gallons of wine. Dissolve the tannin in a small 
amount of wine, add it to the main batch, and mix well. Next, 
dissolve the gelatin with heating in a small quantity of wine, add 
it to the main batch and mix well. Store the wine in a cool place 



n 



(50-60° F). The wine should be clear in 2 weeks to a month. Siphon 
the clear wine from the sediment. Red wines normally contain 
comparatively large amounts of tannin; therefore, it is necessary 
to add only gelatin in order to fine them. 

Aging of Muscadine Wines in Wood 

The question of the desirability of aging IVluscadine wines in 
white oak barrels is often asked by home wine makers. In general, 
we do not recommend this practice in small barrels of 10 gallon 
capacity or less for several reasons: wooden barrels are difficult 
to keep clean and in good repair at home; it is easy to develop an 
excessive "woody" flavor in the wine and/or excessive oxidation 
of the wine stored in small barrels; the rate of evaporation of the 
wine from small barrels is excessively high. There is little doubt, 
however, that proper aging of Muscadine wines in wood will 
generally improve their quality. This is especially true of red 
wines. 

White oak barrels having either a plain or wax inside finish can 
be used to age wine. Charred brandy or whiskey barrels are not 
suitable for aging Muscadine wine. If the home wine maker 
wishes to age his wine in wood, a minimum barrel size of 15 
gallons is suggested. Wooden barrels should be pretreated be- 
fore use. If a new wax-lined barrel is used, fill it full of cool tap 
water in which potassium metabisulfite or sodium bisulfite has 
been dissolved at a rate of five level teaspoons per 10 gallons 
of water. Allow the full barrel to stand for several weeks, then 
drain and rinse it thoroughly several times just prior to use. If 
the barrel has a plain wood finish (not waxed) on the inside, it 
should be soaked for 24 hours with a hot 2% solution of soda ash 
(sodium carbonate), rinsed several times with tap water, and 
filled full with tap water. After several weeks, the barrel should 
be drained, rinsed several times and used immediately. 

If you are aging wine in wood, always keep the barrel filled 
with wine after active fermentation is finished. Wine will evaporate 
from the barrel during storage. Thus once or twice a month the 
amount lost should be replaced, or "topped", from a supply of 
wine in small capacity glass containers saved for this purpose. 
The wine should be tasted once every month so it can be re- 
moved from the barrel if excessive "woody" taste begins to 
develop. 

Preparation of Corks and Bottle Aging of Wine 

If the finished wine is to be stored for any appreciable length 
of time, corked wine bottles should be used. The corks should 
be premium grade, size no. 9, and be either 1 ¥2 or 13/4 inches in 
length. An inexpensive hand corker, which is driven by a mallet, 



18 




Figure 11. 

Corking wine bottles with 
a hand corker which is 
driven by a mallet. 



Figure 12. 

Small corking machine 
operated by levers. The 
lower lever compresses 
the cork and the upper 
one drives it into the bottle. 




19 



can be purchased for a few dollars and is suitable for home use 
(Figure 11). A more elaborate unit, which is operated by levers, is 
convenient to use for a larger number of bottles (Figure 12). The 
corks themselves should be treated before use in the following 
manner. 

Dissolve Va level teaspoon of potassium metabisulfite or sodium 
bisulfite in 2 quarts of hot water. Submerge the corks in the solu- 
tion and allow them to soak 15 minutes. Pour-off the dirty solution 
and replace it with fresh tap water and allow the corks to soak for 
an additional 15 minutes. Pour-off the water, rinse the corks under 
fresh tap water, and allow them to drain thoroughly on a lint free 
cloth or paper towel. The softened corks are ready to use. 

Siphon the wine into the bottles to a level which will allow about 
3/8 inch headspace in the filled bottle after it is corked. Cork the 
bottles and store them in an upright position for 1 week in order 
to allow time for the corks to harden into place. If this is not done, 
some of the bottles will leak. After 1 week, however, the bottles 
should always be stored on their side to keep the corks moist. A 
cool storage temperature of about 50-60° F is desirable. 

Sweetening the Finished Wine 

If a sweeter wine is desired, the wine should be sweetened 
after bottling and aging by adding sugar shortly before use. This 
can be done by dissolving the appropriate amount of sugar in a 
small amount of wine (warming the wine slightly will help) and 
by returning the resulting mixture to the original container of 
wine. The following table should be useful in selecting the amount 
of sugar to add: 



Desired Wine Approximate 
Type % Sugar 



Dry Table 
Mellow Table 
Sweet 



0.25 
3 
10 



Amount of Sugar 

To Add 

(per Vs gallon) 

None 

2 level Tbis. 

6 level TbIs. 



Amount of Sugar 

To Add 

(per gallon) 

None 
V2 Cup 
2 Cups 



If you wish to sweeten the wine before bottling, this can best 
be done at step 19. However, there is an element of risk involved. 
Use this method only when the wine is bright and perfectly clear 
or refermentation may occur after bottling. Be sure to dose the 
wine with potassium metabisulfite or sodium bisulfite as it will 
aid in preventing renewed fermentation after bottling. 



20 



Wine Spoilage 

Conversion of wine into vinegar by vinegar bacteria is one of 
the most common spoilage problems for home wine makers. 
However, if air is excluded from contact with the wine from step 
12 onward, as indicated in the instructions, this type of spoilage 
will not occur. Also, the use of potassium metabisulfite or sodium 
bisulfite inhibits the activities of the vinegar bacteria in the wine. 



HOME WINE MAKING SUPPLIERS 

The following list of companies that sell wine making supplies is 
reprinted from: Wines and Vines, 1971. Directory of the Wine 
Industry, 703 Market Street, San Francisco, California, p. 115. 
No endorsement of these companies is intended or implied by 
the author; the list is reprinted simply as a convenience to the 
reader. 

1. Baird Enterprises & Mfg. Co., 131 Glenn Way, Belmont, Calif. 
94002. 

2. Compleat Winemaker, P. O. Box 2470, Yountville, Calif. 94599. 

3. Fessler, Juluis, P. O. Box 2842, Rockridge Station, Oakland, 
Calif. 94618 

4. Fleming-Potter Company, Inc., 1028 S. W. Adams Street, 
Peoria, 111.61602. 

5. Oak Barrel Winecraft-Winery, 1201 University Ave., Berkeley, 
Calif. 94702. 

6. Presque Isle Wine Cellars, RD No. 1, US Route 20, North East, 
Pa. 16428. 

7. Vino Corporation, P. O. Box 7885, Rochester, NY. 14606. 

8. Wine Art, Inc., 4324 Geary Blvd., San Francisco, Calif. 94118. 



BIBLIOGRAPHY 

(1) Amerine, M. A., H. W. Berg and W. V. Cruess (1967). The 
Technology of Wine Making. 2nd Ed. The AVI Publishing Co., 
Inc., Westport, Conn., p. 799. 

(2) Amerine, M. A. and M. A. Joslyn. (1970) Table Wines. 2nd 
Ed. The AVI Publishing Co., Inc., Westport, Conn. p. 997. 



21 



STATE LIBRARY OF NORTH CAROLINA 




3 3091 00739 0313 



Table 1 



USEFUL CONVERSION FACTORS 
IN WINE MAKING 

Relationship of percent sugar to specific gravity of grape 
juice. 

Percent Sugar Specific 

(by weigtit) 



10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 



Gravity 

1.0381 

1.0423 

1.0465 

1.0507 

1.0549 

1.0592 

1 .0635 

1.0678 

1.0721 

1 .0765 

1.0810 

1.0854 

1.0899 

1 .0944 

1.0990 



Table 2. Relationship of common measures of potassium meta- 
bisulfite or sodium bisulfite to average weight in grams 
and ppm of SO2 generated per gallon wine 

Common Measure Average Weight Amount of SO2 per 

Gallon of Wine 



Vb level Tsp 
Va level Tsp 
V2 level Tsp 
1 level Tsp 



0.64 grams 
1.27 grams 
2.17 grams 
5.63 grams 



100 ppm 
195 ppm 
330 ppm 
870 ppm 



7at>/e 3. Relationship of common measures of gelatin to average 
weight 



Common Measure 

V4 level Tsp 

V2 level Tsp 
1 level Tsp 



Average Weight 
0.60 grams 
1.13 grams 
3.16 grams 



22 



Table 4. Relationship of common measures of tannin (tannic 
acid) to average weight. 



Common l\Aeasure 

Va level Tsp 

V2 level Tsp 
1 level Tsp 



Average Weight 
0.25 grams 
0.45 grams 
1.10 grams 



Table 5. Relationship of common measures of table sugar to 



average weight 
Common Measure 
1 level Tsp 
1 level Tbs 

V2 Cup 
1 Cup 



Average Weight 
4.32 g or 0.1 



,.-^ 3 ..,. -..5 oz. (av.) 

12.05 g or 0.42 oz. (av.) 

105.19 g or 3.7 oz. (av.) 

190.28 g or 6.7 oz. (av.) 



Miscellaneous conversion factors 

1 US gallon of water weighs 8.34 pounds. 

1 US gallon of dry wine weights 8.26 pounds. 

1 US gallon of fresh Muscadine grape juice weighs about 8.8 

pounds. 
8 pints = 4 quarts = 1 US gallon. 
128 ounces (fluid) = 1 US gallon. 
16 ounces (fluid) = 1 pint. 
1 liter = 0.88 quarts. 

1 pound (avoirdupois) = 16 ounces (avoirdupois) = 454 grams. 
1 ounce (avoirdupois) = 28.4 grams. 



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